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java.lang.IllegalStateException: Can't move a node from one state tree to another - Vaadin

Why does I get this error when I close the tab in my web browser and go back to the same URL page again?
Error:
java.lang.IllegalStateException: Can't move a node from one state tree to another. If this is intentional, first remove the node from its current state tree by calling removeFromTree
Cause:
In this case, it's about Vaadin 14 where I'm using the AppLayout class to set its components.
HorizontalLayout firstRow = new HorizontalLayout(loggerId, calibration, alarm, showSamples, samplingTime);
HorizontalLayout secondRow = new HorizontalLayout(do0SliderLayout, do1SliderLayout, do2SliderLayout, do3SliderLayout);
HorizontalLayout thirdRow = new HorizontalLayout(updatePlot, loggingActivate);
thirdRow.setAlignItems(Alignment.CENTER);
VerticalLayout layout = new VerticalLayout(firstRow, secondRow, thirdRow, apexChart);
setContent(layout);
Suggestion:
I think I need to clean up the content before I can set the layout again?
Question:
Do you know how to remove the node from state tree to another?
How to reproduce the error:
Copy over this to your IDE and run the code with Vaadin 14. Access the route, then close your web browser. Open your web browser again and access the route again. This code is a minimal example. I have removed so much I can.
The you will have this error:
#Route("")
#CssImport("./styles/shared-styles.css")
#CssImport(value = "./styles/vaadin-text-field-styles.css", themeFor = "vaadin-text-field")
#Push
#PreserveOnRefresh
public class MainView extends AppLayout {
/**
*
*/
private static final long serialVersionUID = 1L;
public static final String START_LOGGING = "Start logging";
public static final String STOP_LOGGING = "Stop logging";
static public Boolean selectedUpdatePlot = false;
static public Integer selectedShowSamples = 10; // Minimum
static public Integer selectedSamplingTime = 0;
static public Long selectedAID = 0L;
static public Long selectedCID = 0L;
static public Long selectedLoggerId = 0L;
static public ApexCharts apexChart;
static public PaperSlider do0Slider;
static public PaperSlider do1Slider;
static public PaperSlider do2Slider;
static public PaperSlider do3Slider;
static public AtomicBoolean loggingNow;
static public ControlThread control;
#PostConstruct
public void init() {
// Set the top and the tabs
Top top = new Top();
top.setTopAppLayout(this);
// Set the chart
if(apexChart == null)
apexChart = new Graf().getApexChart();
// Create layout for slider 0
if(do0Slider == null) {
do0Slider = new PaperSlider(4095);
}
// Create layout for slider 1
if(do1Slider == null) {
do1Slider = new PaperSlider(4095);
}
// Create layout for slider 2
if(do2Slider == null) {
do2Slider = new PaperSlider(4095);
}
// Create layout for slider 3
if(do3Slider == null) {
do3Slider = new PaperSlider(4095);
}
// This variable controls the logging thread
if(loggingNow == null) {
loggingNow = new AtomicBoolean();
}
// Create control panel
updateControlPanel();
// Start the tread
if(control == null) {
control = new ControlThread(UI.getCurrent());
control.start();
}
}
private void updateControlPanel() {
// Set the logger ids
List<UserLogg> userLoggers = new ArrayList<Long>();
Select<Long> loggerId = new Select<>();
ArrayList<Long> loggerIds = new ArrayList<Long>();
loggerIds.add(selectedLoggerId);
for(int i = 0; i < userLoggers.size(); i++) {
loggerIds.add(userLoggers.get(i).getLoggerId());
}
loggerId.setItems(loggerIds);
loggerId.setValue(selectedLoggerId);
loggerId.addValueChangeListener(e -> {
selectedLoggerId = loggerId.getValue();
});
// Set the calibration id
List<CalibrationLogg> calibrationsLoggers = new ArrayList<Long>();
Select<Long> calibration = new Select<>();
ArrayList<Long> CIDs = new ArrayList<Long>();
CIDs.add(selectedCID);
for(int i = 0; i < calibrationsLoggers.size(); i++) {
CIDs.add(calibrationsLoggers.get(i).getCID());
}
calibration.setItems(CIDs);
calibration.setValue(selectedCID);
calibration.addValueChangeListener(e -> {
selectedCID = calibration.getValue();
});
// Set the alarm id
List<AlarmLogg> alarmsLoggers = new ArrayList<Long>();
Select<Long> alarm = new Select<>();
ArrayList<Long> AIDs = new ArrayList<Long>();
AIDs.add(selectedAID);
for(int i = 0; i < alarmsLoggers.size(); i++) {
AIDs.add(alarmsLoggers.get(i).getAID());
}
alarm.setItems(AIDs);
alarm.setValue(selectedAID);
alarm.addValueChangeListener(e -> {
selectedAID = alarm.getValue();
});
// Slider 0
VerticalLayout do0SliderLayout = new VerticalLayout(new Label("DO0"), do0Slider);
do0SliderLayout.setAlignItems(Alignment.CENTER);
do0Slider.setEnabled(false);
// Slider 1
VerticalLayout do1SliderLayout = new VerticalLayout(new Label("DO1"), do1Slider);
do1SliderLayout.setAlignItems(Alignment.CENTER);
do1Slider.setEnabled(false);
// Slider 2
VerticalLayout do2SliderLayout = new VerticalLayout(new Label("DO2"), do2Slider);
do2SliderLayout.setAlignItems(Alignment.CENTER);
do2Slider.setEnabled(false);
// Slider 3
VerticalLayout do3SliderLayout = new VerticalLayout(new Label("DO3"), do3Slider);
do3SliderLayout.setAlignItems(Alignment.CENTER);
do3Slider.setEnabled(false);
// Sampling time for the thread
IntegerField samplingTime = new IntegerField();
samplingTime.setValue(selectedSamplingTime);
samplingTime.addValueChangeListener(e -> {
if(e.getValue() < 10) {
samplingTime.setValue(10);
selectedSamplingTime = 10;
}
selectedSamplingTime = samplingTime.getValue();
});
// Show amount of samples at the plot
Select<Integer> showSamples = new Select<Integer>();
showSamples.setItems(new Integer[] {10, 20, 30, 40, 50});
showSamples.setValue(selectedShowSamples);
showSamples.addValueChangeListener(e -> {
selectedShowSamples = showSamples.getValue();
});
// Check box if we want to show the plot or not
Checkbox updatePlot = new Checkbox();
updatePlot.setLabel("Plot");
updatePlot.setValue(selectedUpdatePlot);
updatePlot.addValueChangeListener(e -> {
selectedUpdatePlot = updatePlot.getValue();
});
// Start and stop button for logging
Button loggingActivate = new Button(START_LOGGING);
if(loggingNow.get() == true)
loggingActivate.setText(STOP_LOGGING);
loggingActivate.addClickListener(e -> {
if(loggingNow.get() == false) {
loggingActivate.setText(STOP_LOGGING);
calibration.setEnabled(false);
alarm.setEnabled(false);
loggerId.setEnabled(false);
do0Slider.setEnabled(true);
do1Slider.setEnabled(true);
do2Slider.setEnabled(true);
do3Slider.setEnabled(true);
samplingTime.setEnabled(false);
showSamples.setEnabled(false);
updatePlot.setEnabled(false);
loggingNow.set(true);
}else{
loggingActivate.setText(START_LOGGING);
calibration.setEnabled(true);
alarm.setEnabled(true);
loggerId.setEnabled(true);
do0Slider.setEnabled(false);
do1Slider.setEnabled(false);
do2Slider.setEnabled(false);
do3Slider.setEnabled(false);
samplingTime.setEnabled(true);
showSamples.setEnabled(true);
updatePlot.setEnabled(true);
loggingNow.set(false);
do0Slider.setValue(0);
do1Slider.setValue(0);
do2Slider.setValue(0);
do3Slider.setValue(0);
}
});
// Layout
HorizontalLayout firstRow = new HorizontalLayout(loggerId, calibration, alarm, showSamples, samplingTime);
HorizontalLayout secondRow = new HorizontalLayout(do0SliderLayout, do1SliderLayout, do2SliderLayout, do3SliderLayout);
HorizontalLayout thirdRow = new HorizontalLayout(updatePlot, loggingActivate);
thirdRow.setAlignItems(Alignment.CENTER);
VerticalLayout layout = new VerticalLayout(firstRow, secondRow, thirdRow, apexChart);
setContent(layout);
}
}
And a thread
public class ControlThread extends Thread{
private UI ui;
public ControlThread(UI ui) {
this.ui = ui;
}
#Override
public void run() {
while(true) {
}
}
}
Update:
Here is a very minimal code example.
I'm using Vaadin 14.2.1 with OpenJDK 11
#Route("test")
#CssImport("./styles/shared-styles.css")
#CssImport(value = "./styles/vaadin-text-field-styles.css", themeFor = "vaadin-text-field")
public class TestView extends AppLayout {
/**
*
*/
private static final long serialVersionUID = 1L;
static public PaperSlider do0Slider;
#PostConstruct
public void init() {
// Set the slider
if(do0Slider == null) {
do0Slider = new PaperSlider(4095);
}
setContent(do0Slider);
}
}
And the paper-slider from Vaadin dev team.
#Tag("paper-slider")
#NpmPackage(value = "#polymer/paper-slider",
version = "3.0.1")
#JsModule("#polymer/paper-slider/paper-slider.js")
public class PaperSlider extends AbstractSinglePropertyField<PaperSlider, Integer> {
/**
*
*/
private static final long serialVersionUID = 1L;
public PaperSlider(int max) {
super("value", 0, false);
this.getElement().setProperty("max", max);
this.getElement().setProperty("pin", true);
}
}
Notice that if I use this test example:
#Route("test")
#CssImport("./styles/shared-styles.css")
#CssImport(value = "./styles/vaadin-text-field-styles.css", themeFor = "vaadin-text-field")
public class TestView extends AppLayout {
/**
*
*/
private static final long serialVersionUID = 1L;
static public ApexCharts apexChart;
#PostConstruct
public void init() {
// Set the chart
if(apexChart == null)
apexChart = new Graf().getApexChart();
setContent(apexChart);
}
}
With the plot class. I know that Apex Chart's is a third library for Vaadin. But it gives the same error as Paper-Slider.
#Data
public class Graf {
private ApexCharts apexChart;
private XAxis xAxis;
public Graf() {
apexChart = ApexChartsBuilder.get()
.withChart(ChartBuilder.get()
.withType(Type.line)
.withZoom(ZoomBuilder.get()
.withEnabled(true)
.build())
.withToolbar(ToolbarBuilder.get()
.withShow(true)
.build())
.withAnimations(AnimationsBuilder.get()
.withEnabled(false)
.build())
.build())
.withLegend(LegendBuilder.get()
.withShow(true)
.build())
.withDataLabels(DataLabelsBuilder.get()
.withEnabled(false)
.build())
.withColors("#48912c", "#13ebd5", "#215ed9", "#e6c222", "#a524e0", "#633326") // PWM1, PWM2, PMW4, Temp1, Temp2
.withTooltip(TooltipBuilder.get()
.withEnabled(false)
.build())
.withStroke(StrokeBuilder.get()
.withCurve(Curve.straight)
.build())
.withTitle(TitleSubtitleBuilder.get()
.withText("MySQL")
.withAlign(Align.left)
.build())
.withGrid(GridBuilder.get()
.withRow(RowBuilder.get()
.withColors("#f3f3f3", "transparent")
.withOpacity(0.5)
.build())
.build())
.withYaxis(YAxisBuilder.get()
.withTitle(TitleBuilder.get()
.withText("Measurements")
.build())
.build())
.withXaxis(XAxisBuilder.get()
.withTitle(com.github.appreciated.apexcharts.config.xaxis.builder.TitleBuilder.get()
.withText("Time")
.build())
.withCategories("")
.build())
.withSeries(new Series<>("desktop", 1, 2, 3))
.build();
apexChart.setWidthFull();
}
}

One bug related to this was fixed in Vaadin 14.2.1.

RadioGroupButton deselect value when button is clicked in Vaadin 14

I've been working on an online exam project and currently adding some multiple choice feature. My problem is, each time I moved to the next question the value from the previous radiogroupbutton is removed/deselect. But still the assigned value of the object is present.
I tried removing/adding the component as well, still the selected value for the RadioGroupButton is missing.
public class TestQuestionaire extends Dialog {
TQCoverageService tqcs = new TQCoverageServiceImpl();
CellItemService cis = new CellItemServiceImpl();
ItemKeyService iks = new ItemKeyServiceImpl();
VerticalLayout mainLayout;
TQCoverage tqCoverage;
List<CellItem> ciList = new ArrayList();
Map<CellItem, CellItemOption> cellItemAnswerMap = new HashMap();
CellItem cellItem;
Binder<CellItem> binder;
private int tqCoverageId;
private int cellItemIndex = 0;
private int cellItemIndexSize = 0;
private int score = 0;
Button next;
Button prev;
String stem;
Paragraph stemHolder;
RadioButtonGroup<CellItemOption> cioGroup;
public TestQuestionaire(int tqCoverageId) {
this.tqCoverageId = tqCoverageId;
tqCoverage = tqcs.findTQCoverage(tqCoverageId);
cellItemIndexSize = tqCoverage.getTotalItems();
for(TQItems tqi : tqcs.findAllTQItems(tqCoverageId)){
cellItem = cis.findCellItem(tqi.getCellItemId());
List<CellItemOption> cioList = cis.findAllItemOptions(tqi.getCellItemId());
cellItem.setCellItemOptionList(cioList);
ItemKey ik = iks.findItemKey(tqi.getItemKeyId());
cellItem.setItemKey(ik);
TQAnswerKey tqak = tqcs.findTQAnswerKeyByTQItem(tqi.getTqItemId());
cellItem.setTQAnswerKey(tqak);
cellItemAnswerMap.put(cellItem, new CellItemOption());
ciList.add(cellItem);
}
stemHolder = new Paragraph();
stemHolder.setWidthFull();
stemHolder.getStyle().set("font-weight", "500");
Hr hr = new Hr();
hr.setWidthFull();
cioGroup = new RadioButtonGroup<>();
cioGroup.setRenderer(new TextRenderer<>(CellItemOption::getCellItemOption));
cioGroup.addThemeVariants(RadioGroupVariant.LUMO_VERTICAL);
cioGroup.addValueChangeListener(event -> {
if(event.getValue() == null){
return;
}
if(!event.getValue().equals(event.getOldValue())){
cellItemAnswerMap.replace(getCellItem(), event.getValue());
}
});
mainLayout = new VerticalLayout(stemHolder, hr, cioGroup);
mainLayout.setWidth("600px");
hr = new Hr();
hr.setWidthFull();
mainLayout.add(hr);
binder = new Binder();
binder.forField(cioGroup)
.bind(CellItem::getCellItemOption, CellItem::setCellItemOption);
changeCellItem();
prev = new Button(VaadinIcon.BACKWARDS.create());
prev.addClickListener(event -> {
cellItemIndex--;
if(cellItemIndex == 0){
prev.setEnabled(false);
next.setEnabled(true);
} else {
prev.setEnabled(true);
next.setEnabled(true);
}
changeCellItem();
});
prev.setEnabled(false);
next = new Button(VaadinIcon.FORWARD.create());
next.getStyle().set("margin-left", "490px");
next.addClickListener(event -> {
cellItemIndex++;
if((cellItemIndex + 1) == cellItemIndexSize){
next.setEnabled(false);
prev.setEnabled(true);
} else {
next.setEnabled(true);
prev.setEnabled(true);
}
changeCellItem();
});
//this button is only to test if the current value for radiobuttongroup is removed/deselect when clicked!!
mainLayout.add(new Button("TEST", event -> {
changeCellItem();
}));
HorizontalLayout buttons = new HorizontalLayout(prev, next);
buttons.setWidthFull();
buttons.setJustifyContentMode(FlexComponent.JustifyContentMode.START);
mainLayout.add(buttons);
add(mainLayout);
open();
}
//refresh components for new/previous set if item
private void changeCellItem(){
stemHolder.removeAll();
cellItem = ciList.get(getCellItemIndex());
stem = cellItem.getItem().replace("{key}", cellItem.getItemKey().getItemKey());
stemHolder.add(stem);
cioGroup.clear();
cioGroup.setItems(cellItem.getCellItemOptionList());
cellItem.setCellItemOption(cellItemAnswerMap.get(cellItem));
binder.readBean(cellItem);
//binder.setBean(cellItem);
}
public TQCoverage getTQCoverage() {
return tqCoverage;
}
public CellItem getCellItem() {
return cellItem;
}
public int getCellItemIndex() {
return cellItemIndex;
}
public int getCellItemIndexSize() {
return cellItemIndexSize;
}
}

Spring boot app with Vaadin UI constantly refreshing screen

I have a boot app that I am adding some crud screens to. I decided to use Vaadin and it seems to work great until I deploy it to a multi-nodal production environment.
Once in the prod environment the screens constantly refresh for no apparent reason. For example there is a grid in one screen that when a row is clicked a dialog pops up that shows item details. but as soon as the dialog pops up the page refreshes numerous times.
This forum thread here https://vaadin.com/forum/thread/17586129/routerlayout-causing-page-refresh is an example of the same layout I am using and describes a very similar issue.
I have a base abstract class that extends VerticalLayout and all of the concrete classes extend this base abstract class. Each concrete class defines its own route and use a common layout class.
I have reached out on gitter, vaadin forum and opened a bug in github but no one from Vaadin want to respond to anything as far as I can tell.
Here are the versions of everything I am using:
Vaadin Flow version: 14
Java version: 12.0.1+12
OS version: Mac 10.14.5
Browser version: Fire Fox 70.0.1, Chrome 78.0.3904.97
Code snippets from my implementation:
Main View
#Slf4j
#RoutePrefix("v1/crud")
#Theme(value = Material.class, variant = Material.DARK)
public class MainView extends Div implements RouterLayout {
private H1 h1 = new H1("Vaadin Crud UI");
private HorizontalLayout header = new HorizontalLayout(h1);
private Div content = new Div();
private ApplicationContext context;
#Inject
public MainView(ApplicationContext context) {
this.context = context;
setSizeFull();
h1.setWidthFull();
content.setWidthFull();
header.setWidthFull();
header.setAlignItems(FlexComponent.Alignment.CENTER);
VerticalLayout navigationBar = new VerticalLayout();
navigationBar.setWidth("25%");
navigationBar.add(createNavigationButton("Home", VaadinIcon.HOME, ReportTab.class));
navigationBar.add(createNavigationButton("Batch Search", VaadinIcon.SEARCH, BatchSearchTab.class));
... a bunch more buttons
HorizontalLayout layout = new HorizontalLayout(navigationBar, content);
layout.setWidthFull();
VerticalLayout page = new VerticalLayout(header, layout);
page.setWidthFull();
add(page);
}
#Override
public void showRouterLayoutContent(HasElement hasElement) {
if (hasElement != null) {
Element newElement = hasElement.getElement();
if (newElement != null) {
content.removeAll();
content.getElement().appendChild(newElement);
}
}
}
private Button createNavigationButton(String caption, VaadinIcon icon, Class<? extends BaseEditor> editor) {
Button button = new Button(caption, icon.create());
button.addClickListener(event -> UI.getCurrent().navigate(editor));
button.addThemeVariants(ButtonVariant.MATERIAL_CONTAINED);
button.getStyle().set("background-color", "#00819D");
button.setWidthFull();
return button;
}
}
Base Component:
#Slf4j
#Data
#SpringComponent
#UIScope
public abstract class BaseEditor<P, B> extends VerticalLayout {
private final RememberMeService rememberMe;
private final P businessProcess;
protected Binder<B> binder;
protected Dialog editDialog = new Dialog();
protected Button save = new Button("Save", VaadinIcon.CHECK.create());
protected Button close = new Button("Close", VaadinIcon.EXIT.create());
protected Button delete = new Button("Delete", VaadinIcon.TRASH.create());
protected B bean;
private ChangeHandler changeHandler;
private boolean proceed = true;
public BaseEditor(P businessProcess, RememberMeService rememberMe) {
this.rememberMe = rememberMe;
this.businessProcess = businessProcess;
save.addClickListener(e -> save());
delete.addClickListener(e -> delete());
}
public abstract void delete();
public abstract void save();
protected abstract Component getContent();
protected void edit(B e) {
bean = e;
editDialog.open();
getBinder().setBean(e);
}
protected void initEditorPanel(Component... components) {
HorizontalLayout actions = new HorizontalLayout(save, close, delete);
VerticalLayout data = new VerticalLayout(components);
data.add(actions);
editDialog.removeAll();
editDialog.add(data);
getBinder().bindInstanceFields(this);
close.addClickListener(e -> editDialog.close());
}
public interface ChangeHandler {
void onChange();
}
void setChangeHandler(ChangeHandler h) {
changeHandler = h;
}
void errorDialog(String message) {
final Button close = new Button("Close", VaadinIcon.CLOSE.create());
H3 h3 = new H3(message);
final Dialog errorDialog = new Dialog(h3, close);
errorDialog.open();
close.addClickListener(e -> errorDialog.close());
}
BaseEditor filter(Predicate<B> predicate) {
Objects.requireNonNull(predicate);
proceed = predicate.test(bean);
return this;
}
void buttonConsumer(Consumer<B> consumer) {
if (!proceed) {
proceed = true;
return;
}
try {
consumer.accept(bean);
} catch (Exception e) {
errorDialog(e.getMessage());
} finally {
editDialog.close();
getChangeHandler().onChange();
}
}
void either(Consumer<B> whenTrue, Consumer<B> whenFalse) {
try {
if (proceed) {
whenTrue.accept(bean);
} else {
whenFalse.accept(bean);
}
} catch (Exception e) {
errorDialog(e.getMessage());
} finally {
proceed = true;
editDialog.close();
getChangeHandler().onChange();
}
}
}
Concrete Component:
#Slf4j
#Route(value = "search/batch", layout = MainView.class)
public class BatchSearchTab extends BaseEditor<BatchService, Batch> {
private TextField searchField1;
private TextField searchField2;
public BatchSearchTab(BatchService businessProcess, RememberMeService rememberMe) {
super(businessProcess, rememberMe);
binder = new Binder<>(Batch.class);
save.setIcon(VaadinIcon.REPLY.create());
save.setText("Replay");
delete.setIcon(VaadinIcon.CLOSE.create());
delete.setText("Cancel");
getContent();
}
#Override
public void delete() {
buttonConsumer(b -> getBusinessProcess().cancelBatch(b.getBatchId(), b.getUserAgent()));
}
#Override
public void save() {
filter(b -> b.isReplayable()).buttonConsumer(b -> getBusinessProcess().buildAndSendFile((getBean())));
}
#Override
public void edit(Batch batch) {
HorizontalLayout actions = new HorizontalLayout();
H2 h2 = new H2();
if (batch.isReplayable()) {
h2.setText("Would you like to replay the following.");
actions.add(save, delete, close);
} else {
h2.setText("This record is not eligible for replay.");
actions.add(close);
}
Label batchId = new Label("Correlation Id: " + batch.getBatchId());
Label txnCount = new Label("Transaction Count: " + batch.getTotalTxns());
Label txnAmount = new Label("Total: " + batch.getTotalBatchAmount());
VerticalLayout data = new VerticalLayout(h2, batchId, txnCount, txnAmount, actions);
data.add(actions);
editDialog.removeAll();
editDialog.add(data);
close.addClickListener(e -> editDialog.close());
editDialog.open();
getBinder().setBean(batch);
}
#Override
protected Component getContent() {
final H2 h2 = new H2("Locate Batches");
searchField1 = new TextField("Batch Code");
searchField2 = new TextField("User Agent");
searchField2.addKeyPressListener(Key.ENTER, e -> keyPressListener());
Button searchBtn = new Button("Search", VaadinIcon.SEARCH.create());
HorizontalLayout search = new HorizontalLayout(searchField1, searchField2);
searchBtn.addClickListener(e -> {
search(searchField1.getValue(), searchField2.getValue());
});
add(h2, search, searchBtn);
return this;
}
private void search(String code, String userAgent) {
log.info("Searching {} and {}", code, userAgent);
List<Batch> batches =
getBusinessProcess().getBatchesForUserAgent(code, userAgent, 60);
log.info("Found {} batches", batches.size());
if (batches.size() > 0) {
buildGrid(batches, "BatchId", "totalTxns", "totalBatchAmount", "status");
} else {
errorDialog("No Records found for criteria");
}
}
private void keyPressListener() {
String code = StringUtils.isNotBlank(searchField1.getValue()) ? searchField1.getValue() : null;
if (StringUtils.isNotBlank(searchField2.getValue())) {
search(code, searchField2.getValue());
}
}
private void buildGrid(Collection<Batch> records, String... columns) {
Component result;
if (records.size() == 0) {
result = new Label("NO REPORT DATA AVAILABLE.");
} else {
final Grid<Batch> grid = new Grid<>(Batch.class);
grid.setHeightByRows(records.size() < 10);
grid.setColumns(columns);
grid.setItems(records);
grid.setWidthFull();
grid.asSingleSelect().addValueChangeListener(l -> Optional.ofNullable(l.getValue()).ifPresent(this::edit));
result = grid;
}
if (getComponentCount() < 3) {
add(result);
} else {
replace(getComponentAt(2), result);
}
}
private void loadData(String code, String userAgent) {
if (StringUtils.isNotBlank(code)) {
search(null, userAgent);
} else {
search(code, userAgent);
}
}
}

Disclaimer: some further fact finding happended via IRC
The answer to the question is related to OP running multiple instances of the application behind an round robin load ballancer. The clients hit random servers and therefor had no session running there.
The solution to this is having a shared session store and ideally have the load ballancer dispatch on existing session, so "hot" backend servers get hit.

Search filter in Container Codename One

I'm trying to implement a search filter in my Container which contains a set of buttons.
Here's my code:
public void listMenu() {
Dialog loading = new InfiniteProgress().showInifiniteBlocking();
loading.show();
final Form listMenu = new Form("List Menu");
listMenu.setLayout(new BoxLayout(BoxLayout.Y_AXIS));
Container list = new Container();
list.setLayout(new BoxLayout(BoxLayout.Y_AXIS));
list.removeAll();
Button back = new Button("Back to Main Menu");
ParseQuery<ParseObject> query = ParseQuery.getQuery("mylist");
query.whereExists("Title");
List<ParseObject> results = null;
try {
Button btn = null;
results = query.find();
if(!results.isEmpty()) {
int index = 0;
int size = results.size();
for(;index < size;++index) {
list.add(btn = new Button(results.get(index).getString("Title")));
addListener(btn);
}
}
} catch (com.parse4cn1.ParseException e) {
Dialog.show("Err", "Server is not responding.", "OK", null);
}
listMenu.add(list);
listMenu.add(back);
listMenu.show();
loading.dispose();
back.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ev)
{
new StateMachine("/theme");
}
});
}
This code basically is querying data from the Database then setting its results into buttons then added to a Container. My question is how to implement a search filter to my Container? I've seen FilterProxyListModel<T> but not sure if ListModel<T> is compatible with Container. I'd appreciate to see an example of search filter implementation in my code.

FilterProxyListModel is for List which we don't recommend anymore. There is a full sample of searching a container here. It uses MultiButton but using Button would work just as well:
hi.getToolbar().addSearchCommand(e -> {
String text = (String)e.getSource();
if(text == null || text.length() == 0) {
// clear search
for(Component cmp : hi.getContentPane()) {
cmp.setHidden(false);
cmp.setVisible(true);
}
hi.getContentPane().animateLayout(150);
} else {
text = text.toLowerCase();
for(Component cmp : hi.getContentPane()) {
Button mb = (Button)cmp;
String line1 = mb.getText();
boolean show = line1 != null && line1.toLowerCase().indexOf(text) > -1;
mb.setHidden(!show);
mb.setVisible(show);
}
hi.getContentPane().animateLayout(150);
}
}, 4);

Tree View JavaFX Memory out of Space

I have created javaFX tree with custom Objects (SystemNode).
Tree Items has graphics: check-box and image icon which I have set through updateItems() method.
Whenever I expand or collapse Item in tree ,twice or thrice I get JAVA HEAP MEMORY OUT OF SPACE and whole UI hangs UP.
PS: updateItems() method is invoked every time I expand or collapse tree node
I have tried adding event handlers but they didn't work.
Can anyone give some solutions.
Here is how I set cellFactory :
treeView_technicalAreas.setCellFactory(Util.getTreeCellFactory());
Here is code for cell factory:
public static Callback<TreeView<SystemNode>, TreeCell<SystemNode>> getTreeCellFactory() {
Callback<TreeView<SystemNode>, TreeCell<SystemNode>> callback = new Callback<TreeView<SystemNode>, TreeCell<SystemNode>>() {
#Override
public TreeCell<SystemNode> call(TreeView<SystemNode> p) {
TreeCell<SystemNode> cell = new TreeCell<SystemNode>() {
#Override
protected void updateItem(SystemNode t, boolean isEmpty) {
super.updateItem(t, isEmpty); //To change body of generated methods, choose Tools | Templates.
if (!isEmpty) {
System.out.println("util call back : " + t.getSystem().getName());
setText(t.getSystem().getName());
HBox hBox = new HBox();
CheckBox checkBox = new CheckBox();
checkBox.setSelected(t.getSelected());
checkBox.selectedProperty().bindBidirectional(t.getSelectedProperty());
hBox.setSpacing(SPACING_BETWEEN_ICON_AND_CHECKBOX);
ImageView imageView_icon = null;
if (t.getSystem().getType() == TYPE.BAREA) {
imageView_icon = new ImageView(Constant.Image_AREAS);
} else if (t.getSystem().getType() == TYPE.AREA) {
imageView_icon = new ImageView(Constant.Image_AREAS);
} else if (t.getSystem().getType() == TYPE.DOCUMENT) {
imageView_icon = new ImageView(Constant.Image_DOCUMENTS);
} else if (t.getSystem().getType() == TYPE.NOUN_NAME) {
imageView_icon = new ImageView(Constant.Image_NOUN_NAME);
} else if (t.getSystem().getType() == TYPE.CHANGE) {
imageView_icon = new ImageView(Constant.Image_DCC);
} else if (t.getSystem().getType() == TYPE.TASK) {
imageView_icon = new ImageView(Constant.Image_TASK);
}
hBox.getChildren().addAll(checkBox, imageView_icon);
setGraphic(hBox);
}
}
};
return cell;
}
};
return callback;
}